Fluid flow regulating valve



Sept 7, 1965 D. GoRcHEv ETAL 3,204,664

FLUID FLOW REGULATING VALVE Filed March 16, 1962 2 Sheets-Sheet 1 SePt-7, 1965 D. GoRcHEv ETAL 3,204,664

FLUID FLOW REGULATING VALVE Filed March 16', 1962 2 Sheets-Shea?I 2 Z?74 if ,BLovvER f g United States Patent O '3,204,664 FLUD FLW REGULATINGVALVE Dimiter Gorcliev and 'Hend Gorcliev, both of 5 Washington Ave.,Cambridge, Mass. Filed Mar. `16, 1962, Ser. No. 180,136 3 Claims. (Cl.13S-416) This is a continuation-in-part of my application Serial No.102,747, filed April 13, 1961, now abandoned, which is acontinuation-in-part of application Serial No. 30,330, iiled May 19,1960, now abandoned.

The field of this invention is that of regulated fluid supply systemsand regulating valves, and the invention relates more particularly tovalves for maintaining constant volume fluid flow in a conduit, and to asystem utilizing valves of this type.

In forced air heating or air conditioning systems it is desirable thatthe flow of air into any particular area be controlled locally as by athermostat. The varying demands thus placed on the system by multiplelocal controls may introduce substantial fluctuations of the airpressure in the supply mains. If no steps are taken to counteract thesefluctuations, each local adjustment may affect the balance of the entiresystem, causing short term variations in the supply of air to at leastsome of the other areas, which variations tend to be physiologically andpsychologically more disturbing in terms of draft and noise sensationsthan the relatively less frequent variations introduced by the localcontrol apparatus. One attempt to rectify this dilliculty has been toplace a pressure-sensitive central control device on the main pressuresupply which will, for example, regulate a main fan so as to maintainits output at constant pressure. Such systems however do not alleviatethe above mentioned disturbances since the varying local demand causeslocal pressure fluctuations due to the varying volume of air being drawnthrough substantial lengths of duct work between the outlets and thecontrol point. Thus the added expense of central control is largelywasted for this purpose.

Objects of the present invention are to provide a valve which canmaintain the local volume of flow constant, independently of thepressure existing in the supply mains; to provide such a valve which canbe adjusted over a relatively wide range so that it can be used also toprovide local control, which can be conveniently and accurately soadjusted, and whrich can be inexpensively manufactured and installed; toprovide a ow regulating valve which can be utilized inA a forced airsystem without introducing excessive resistance to air flow under normalconditions; to provide such a value which is not subject to rapid Wearor fatigue; and to provide such a valve which will not be easily fouledor clogged with extraneous matter such as might be carried by fluidflowing through the value.

Further important aspects of the invention are to provide an air supplysystem in which the delivery of air to any particular area can belocally controlled independently of the conditions existing in any otherarea; to provide such a system wherein local air supply at anyparticular area is not disturbed by regulation at another area; and toprovide such a system which does not require central regulation andoperates at least just as well Without central regulation.

The substance of the invention can be briefly summarized in some of itsaspects as follows.

In a principal aspect, a valve according to the invention comprises asubstantially tubular member adapted to be connected within a conduct, aplunger member supported coaxially within the tubular member therebydefin- "ice ing a fluid passage between the two said members, the mannerof support permitting movement of the plunger parallel to the flow andat least one of the members being tapered so that movement of theplunger member in the direction of flow will reduce the size of saidfluid passage, and spring means for urging the plunger member againstthe drag of a iiuid ow.

In a practically important aspect the valve according to the inventionincludes viscous damping means, such as a duid filled bellows, forchecking oscillatory movement of the plunger member.

In another practically important and more specific aspect of theinvention, the valve plunger member has an axial bore receiving a shafthaving an adjustable collar, spring means being mounted on the shaftbetween the collar and a hub of the plunger for urging the plunger awayfrom the collar against restraining means at the end of the shaftwhereby, by adjusting the position of the collar, the plunger can beadapted for movement as above described in response to selected pressuredifferentials. In a preferred embodiment, the shaft is slidably mountedin bearings which are fixed relative to the tubular member, which has aconstricted bore portion, and for purposes of adjustment the shaft andconduit are provided with suitable means such as a raclf` and pinionwhich can be easily adjusted so as to fixate the plunger and tubularmembers relatively to each other from without the conduit. In thismanner, movement of the plunger on the shaft can be adapted to occurwithin a selected part of the bore portion of the tubular member.

These and other objects, aspects, advantages and results of theinvention will appear from the following detailed description of severalpractical embodiments thereof illustrating its novel characteristics.

The description refers to drawings in which FIG. 1 is a` side elevationview, partiallyin section, of a valve according to the invention;

FIG. 2 is a partial section view similar to FIG. 1 showing analternative embodiment of the valve provided by the invention;

FIG. 3 is a section view along line 3 3 of FIG. 1;

FIG. 4 is a partial section view, to enlarged scale, along thelongitudinal axis ofthe valve plunger illustrated in FIG. 2;

FIG. 5 is a diagrammatic illustration of an air supply system; and

FIG. 6 is a sideV elevation view, in section, of another valve.

Referring to the drawing, FIG. 1 illustrates one embodiment of the flow=regulating valve according to this invention wherein the valve ismounted within a conduit indicated by the broken lines 11 and 12', :inwhich fluid flow occurs between' an area of relatively high fluidpressure and an area of relatively low fluid pressure in the directionindicated by the arrows f. As will be readily understood, the fluid flowvelocity through the valve is determinedl by the fluid pressuredifferential thereacross. As illustrated, the valve is particularly welladapted for regulating air flow through the conduit 11, 12 but it shouldbe understood that the valve is also well suited for regulating the flowof other gases and liquids if proper means are provided for forming aseal between the valve and the conduit.

The valve includes a tubular member 16 having portions of reduceddiameter, as at 16.1, which are adapted to form lapped joints withcorrespondingly grooved portions 121 of the conduit 12, and can beconveniently secured within the conduit 12 by means of force fittingwith the matching conduit grooves, as shown, or by any other suitablemeans such as soldering, cementing or bolting at 14. The tubular memberhas a bore portion 16.2 of a selected length m which converges from afluid inlet opening or end 16.3 of a cross-sectional area andconfiguration corresponding to that of the conduit to an outlet end 16.4of smaller cross-sectional area. The converging bore portion can beembodied in an individual sleeve 17 forcetted within the tubular memberas shown or can vbe provided as an integral part of the tubular member,

the taper of the bore portion being adapted to constrict iuid flowthrough the con-duit without creating turbulence in the conduit adjacentthe iiuid inlet opening 16.3, as at the region indicated by asterisk 18.

The valve further includes a plunger 20 having a base portion 20.1 and anose portion 20.2 which diverges in the direction of ow towards the basefor a distance n. As shown particularly in FIG. 4, the plunger 20 has ahub 22 near its base. This hub has a base bushing 22.1 and is held byseveral, such as three, legs 22.2. The tip of the plunger 20 has aperforation with a tip bushing 22.5.

At the end of shaft 24 is a nose collar means such as a retaining ring24.2 which keeps the bushing 22.5 on the shaft. A hub collar means 23 isadjustably secured to the shaft 24, for example by means of a set screw23.1 and a coil spring 36 is disposed on the shaft between the collar 23and the hub bushing 22.1 for biasing the plunger to oppose movement inthe direction of fluid ow. The adjustable collar 23 can be positioned onthe shaft which is mounted relatively to the tubular member as will bedescribed below, so that the spring 36 holds the plunger in the positionshown in full lines in FlG. 1, for example, against a selecteddifferential in the iiuid pressures exerted on the base and noseportions of the plunger, thereby to permit a selected volume of fluid tomove through the restricted passage indicated at p. If uid pressure inthe conduit increases, the force exerted on the plunger nose portionwill also increase thereby moving the plunger against the bias of thespring 36 to the position shown, by Way of example, in dotted lines inFIG. 1. This plunger movement reduces the passage to the size indicatedat q and it Will be readily understood that the taper of the boreportion 16.2 can be proportioned with respect to the characteristics ofthe spring 36 as set by collar 23 such that reduction of the passagesize from that indicated at p to that indicated at q compensates for theincreased pressure differential across the restricted passage, wherebythe fluid volume moving through the passage will be constant for thatspring setting and a given position of shaft 24. Since the resistance ofthe system downstream of the valve is by nature constant, the constantvolume llow passed by the valve tends to make the discharge pressure atthe valves outlet constant also.

T he nose portion 20.2 of the plunger extends oppositely of thedirection of fluid flow as shown and is tapered or faired to conduct uidiow within the uid passage partially defined by the plunger base withoutcreating turbulence within the conduit as at point 18. Further, as thenose portion is of a length exceeding that of the converging boreportion 16.2 of the tubular member, the nose portion will extend withinan area of the conduit which is free of turbulence even when the plungerbase is located at the outlet end 16.11` of the bore portion.

For permitting adjustment of the volume which is at any given time keptconstant by the valve, the shaft 24 is slidably mounted in a sleevebearing 38 which is supported in coaxial relation to the tubular member16 by spider supports 38.1 the ends of which are riveted or otherwisefastened to the tubular member, as at 38.2. The shaft is provided with arack section as at 24.5 and a pinion 40 is mounted upon a shaft 42extending across the tubular member for cooperation with the shaft rack.The shaft 42 is rotatably supported in suitable bearings of the tubularmember and has a control extension 42.1 which can be actuatedcontinuously or at times from outside the valve, manually or by motormeans (not shown) for rotating the pinion to move the shaft 24 in thebearing 38. Thus the bias of the spring 36 can be set, and the limits oftravel of the plunger 20 can be adjusted externally. By means of thisadjustment, as distinct from the above described initial adjustment bymeans of the collar 23 for setting a constant volume for a givenposition of shaft 24, the size of the restricted Huid passage whichcorresponds to a given pressure differential can also be adjusted andaccordingly the volume rate of ow which the valve tends to maintain canbe adjusted to conform to any value determined by external control meansas will be described by way of example with reference to FG. 5.

It will be seen that the valve provided by this invention is ofinexpensive and yet rugged construction and that the valve can beconveniently adjusted over a wide range and is accurately responsive tovariations in operating condition for providing constant uid flow volumethrough the conduit. It will also be seen that, since the valve isadapted to regulate fluid flow without creating turbulence in theconduit and without requiring long fluid passages which are narrowlyconstricted, the valve does not introduce excessive resistance to fluidflow in the conduit under normal conditions. Further, the valveadjusting means are not likely to be clogged with lint or otherextraneous matter which might be carried in the fluid flowing throughthe valve.

An alternative embodiment of the valve according to this invention isillustrated in FIG. 2. In this embodiment of the invention, the tubularmember 56 is secured within the conduits 51, 52 by means of screws 54,and the constricted bore 56.2 of the tubular member is formed by ashaped, such as molded, portion of one of the conduit members itself.The inwardly converging bore portions of this tubular member have aninlet opening 58 and an outlet opening 59 which correspond inconguration and cross-sectional area to those of the conduits 11, 12,with an intermediate portion 60 of appropriate smaller crosssectionalarea. In this construction, the plunger is adapted for movement throughthat portion of the converging bore 56.2 which extends from the inletend 58 to the smaller portion 60 in the same manner as described abovewith reference to FIG. l, that portion of the converging bore betweenthe narrow portion 66 and the outlet end 59 serving further to reduceturbulence of uid ow through the valve. Preferably also, the edge 65.1of the plunger base is rounded to reduce turbulence which might becreated by the valve means.

An improved air supply system in which the abovedescribed valves areparticularly useful will now be described with reference to FIG. 5. Byway of example, this could be an air conditioning system which suppliesmore air, cooled to a substantially constant temperature, if theregional temperature increases such as due to turning on of lamps,increased number of occupants, or warmer outside temperature, or viceversa.

A blower 70, taking in air from any conventional cooling or heatingapparatus (not shown), is arranged to feed a plurality or" ducts '72.The ducts are connected to outlets 74 through valves 76 preferably ofthe above-described types, these valves being controlled locally bymeans of thermostats 78 so that the system provides a suitable amount ofair to each area. One of the valves is diagrammatically shown accordingto FIG. 2, with a tubular member 56 having a constricted portion 6),with a plunger 65, a rod 24, a spring 36, and a shaft 42. A regulatingmotor M sits on shaft 42 and is controlled by one of the thermostats 7S.As explained previously, even if the blower 71B were regulated so as toprovide a constant output pressure, the varying demands placed upon thesystem through the ducts 72 would produce local fluctuations in pressuresince the ducts possess an appreciable resistance to flow, withdetrimental results if valves were used which do not maintain constantvolume for each local demand setting. If, however, the valves are of atype which pass a constant volume of fluid over a range of supplypressures such as valves described above with reference to FIGS. 1 to 4,these local fluctuations of pressure will not affect local deliveryrates. Furthermore,

this favorable mode of operation will exist even if the blower 70 is notregulated but rather is permitted to deliver air according to itsnatural characteristic.

Another alternative and particularly effective construction of valvesaccording to the invention is shown in FIG. 6. In this and analogousembodiments the tubular member or duct 80 is preferably constructed ofmetal, such as aluminum, tubing and the constricted portion 81 of itsbore is formed by spinning. A shaft 82 is coaxially and slidablysupported within the tubular member by apertured cross bars 83, 84suitably fastened to the duct 80, such as by screws 84.1. Slidablymounted on the shaft is a hollow, rounded plunger member 85 preferablyalso constructed of spun aluminum in two parts 85.1 and 85.2 which aresecured together by sheet metal screws 84. Suitable bushings 87.1, 87.2of appropriate for example synthetic bearing material are provided forguidance on the shaft 82 and these bushings are held to the plungermember by C-shaped clips 91, 93.

Within the plunger member 84 is a coil spring 88, one end of which restsagainst a stop 89 which is prevented from moving relative to the shaft82 by a C-shaped clip 79 and the other end of which rests on a dishedportion 85.3 of the plunger part 85.2, urging the plunger member 85 inan upstream direction. Behind the plunger member 85, with reference tothe direction of ow, is a bellows 90 constructed of elastic materialsuch as neoprene and filled with a viscous fluid such as air. One end ofthe bellows is attached to the plunger member 85.1, by means of theabove mentioned bushing 87 and the C-shaped clip. 91. The other end ofthe bellows is secured to the shaft 82 by C-shaped clips 9 (only one ofwhich is shown) which fit corresponding grooves in the shaft 82, oneither side of the bellows wall where it adjoins the shaft. At one endof the bellows 90 is provided a metal vent 99 which permits air to passinto or out of the bellows at a substantially predetermined amount andpressure.

The position of the shaft 82 can be adjusted in the direction of ow bysuitable motor means, such as a pneumatic motor 101 mounted on aplatform 102 secured to the duct 80 and operating through the links 105and 106 and the lever 107 in conventional manner. The lever 107 ishinged to the duct 80, apertured at 80.1, by means of a divided bridge111 and a pivot pin 112. It will be evident that the bellows 90 asherein described, provides the viscosity function of a uid which resistschange in its shape or in arrangement of its elements during How; thiscomponent therefore constitutes and is referred to herein also as aviscous dampening means. The aperture 80.1 is sealed around the lever107 by a flexible bellows 115 which can conveniently be of the sameshape and material as bellows 90, although it has a different function.

The basic operation of the valve according to FIG. 6

is similar to the embodiments shown in FIGS. 1 to 4. Flow of air throughthe valve in direction f exerts a drag on the plunger member pushing itback against the force of the spring 88. This movement causes acontraction of the uid passage between the plunger member and theconstricted portion 81 of the tubular member 80. By a proper shaping ofthe taper of the constrictedI position 81 with respect to thecharacteristics of the spring 88 as set by clip 79, the valve willoperate so as to pass a substantially constant volume of air for anappreciable variety of dierential pressures existing across the valve.The bellows 90, not included in the above embodiments, provides viscousdampening of the movement of the plunger member so that, in certainapplications which would otherwise lead to instable operation, the valvewill not oscillate. The amount of damping depends, of course, on thesize and configuration of the vent 99. In some situations the desiredventing may be obtained merely through the clearance between the rearplunger bushing 87.1 and the shaft 82, and such a construction should beunderstood to be within the scope of the invention.

It will now be evident that constant volume valves according to theinvention and centrally unregulated fluid control systems incorporatingsuch valves offer the following advantages and appreciably improvedresults among others similarly appearing from the above exposition ofthe substance and nature of the invention and from the description ofseveral embodiments thereof.

The valves according to the invention permit easy and accuratecontinuous adjustment within a wide range as determined by a regulatingdevice such as a thermostat, and they automatically maintain essentiallyconstant volume and discharge pressure for any such adjustment.Furthermore, they accomplish this with simple means, without causingturbulence and substantial resistance losses.

Fluid control systems incorporating such valves provide optimalregulation without physiological and psychologically detrimentaleffects, in addition to the advanta-ges individually inherent in eachvalve, and in addition to the economic advantages of such optimaloperation without central control. It should be noted that systems withconventional regional regulation, without as well .as with centralregulation exhibit the herein outlined defects whereas systems accordingto the present invention not only obviate central regulation with itsinitial cost and often cumbersome maintenance and unreliability but, inspite of the omission of central regulation, provide superioroperational characteristics. As will now be evident, this is due to thefact that systems according to the invention provide optimal regionalvolume and discharge pressure regulation without affecting the otherregions, as contrasted with central regulation systems whereinregulation at any region is likely to have detrimental effects on anyother region.

While the system described above by way of example contemplates fairlyysimple regulation by way of thermostatically controlled supply of coldair, it will be understood that the invention is applicable to morecornplex systems such as using in addition temperature control of thesupplied air, or individually controlled supplemental heat sources asfor example regional radiators.

Although particular embodiments of the valve provided by this inventionhave been described for the purpose of illustration, it should beunderstood that the invention includes all modifications and equivalentsthereof which fall within the scope of the appended claims.

We claim:

1. A valve for regulating a fluid flow comprising:

a substantially tubular member adapted to be connected within .aconduit;

a shaft mounted coaxially within said member;

a plunger member slidably mounted on said shaft thereby defining a uidpassage between the two said members, at least one of said tubular andplunger members, respectively, having a taper such that movement of theplunger member in the direction of flow will reduce the size of saidfluid passage;

a coil spring coaxial with said .shaft one end of which is connected tothe shaft and the other end of which urges said plunger member in thedirection opposing the drag of a uid iiow, said taper beingpredetermined with respect to the characteristics of said spring so asto maintain ow through the valve at a constant volume over a substantialrange of pressure differentials;

a bellows coaxial with said shaft one end of the bellows being connectedto the shaft .and the other end of the bellows being connected to saidplunger member; and

a vent of predetermined conguration connecting the interior and exteriorof said bellows;

whereby the movement of said plunger member in response to pressuredifferentials is viscously damped.

2.. A valve for regulating a fluid ilow comprising: a substantiallytubular member .adapted to be connected within a conduit;

a shaft mounted coaxially within said member; a hollow, rounded plungermember slidably mounted a coil spring coaxial with said shaft andcontained Within said plunger member, one end of the spring beingconnected to the shaft and the other end of the spring bearing on saidplunger member thereby urging said plunger member in the directionopposing the drag of a fluid flow, said taper being predetermined withrespect to the characteristics of sai-d spring so as to maintain flowthrough the valve at a 20 constant volume over a substantial range ofpressure differentials;

a bellows coaxial with said shaft one end of which is connected to theshaft and the other end of which is connected to said plunger member;and a vent of predetermined configuration connecting the interior andexterior of said bellows, whereby movement of said plunger member inresponse to varying pressure diierentials is viseously damped. 3. Avalve according to claim 2 including means for adjusting the position ofsaid shaft in the direction of flow.

References Cited bythe Examiner UNITED STATES PATENTS l,635,040 7/27Fales 13S-46 2,925,826 2/60 Streeter 137-517 2,929,402 3/60 Streeter137-517 2,941,401 6/60 Streeter 137-517 2,956,583 lO/6O Slreeter137--517 FOREIGN PATENTS 670,839 4/52 Great Britain. 326,792 6/35 Italy.

LEWIS J. LENNY, Primary Examiner.

EDWARD V. BENHAM, Examiner.

1. A VALVE FOR REGULATING A FLUID FLOW COMPRISING: A SUBSTANTIALLYTUBULAR MEMBER ADAPTED TO BE CONNECTED WITHIN A CONDUIT; A SHAFT MOUNTEDCOAXIALLY WITHIN SAID MEMBER; A PLUNGER MEMBER SLIDABLE MOUNTED ON SAIDSHAFT THEREBY DEFINING A FLUID PASSAGE BETWEEN THE TWO SAID MEMBERS, ATLEAST ONE OF SAID TUBULAR AND PLUNGER MEMBERS, RESPCETIVELY, HAVING ATAPER SUCH THAT MOVEMENT OF THE PLUNGER MEMBER IN THE DIRECTION OF FLOWWILL REDUCE THE SIZE OF SAID FLUID PASSAGE;